Teck Resources is already a significant copper producer with Highland Valley Copper and Carmen de Andacollo, but of course it is now moving forward again with QB2 which as part of the discussion around the project’s recent online virtual site visit was described by Donald R. Lindsay, Teck President, Chief Executive Officer & Director as “the cornerstone,” adding “we have one of the very best copper production growth profiles in the industry.” QB2 start-up in the second half of next year will double Teck’s consolidated copper production by 2023. Following the completion of QB2, Teck’s base metals business is expected to grow by more than 60% to more than 850,000 t in 2023 as measured in copper equivalent production.
The QB2 project is owned by Compañía Minera Teck Quebrada Blanca SA (QBSA), itself owned by operator Teck (60%), Sumitomo Metal Mining Co Ltd and Sumitomo Corporation (30%), and Enami, a Chilean State agency (10%). Bechtel is managing all aspects of EPCM services and construction contractors, including the integration of third party engineering providers, suppliers and vendor representatives to complete the pre-operational testing to mechanical completion and handover.
The supergene orebody (near-surface deposit) was mined during the initial phase of Quebrada Blanca. QB2 will develop the deeper sulphide resource underlying the existing operation. As a result, QB2 is effectively pre-stripped, which greatly reduces project costs. The initial 28-year mine life will use only 25% of total reserves and resources to a maximum pit depth of 720 m. In addition, it has an exceptional strip ratio of 0.7 over the mine life, meaning that only 0.7 t of waste needs to be mined (0.44 over the first five full years) for every one tonne of ore mined. The operation will be managed from a Remote Integrated Operations Centre located in Santiago which opened in Q1 2020. The project includes new port facilities on Chile’s coast near Punta Patache, where future product will be loaded for shipment to customers around the world. The desalination plant, also located in the port area, will be the first large-scale use of seawater in place of fresh water in the Tarapacá Region. Major infrastructure installations will connect the mine area to the port facilities, with over 165 km of pipelines to transport fresh water to the mine and concentrate back to the port. A 220 kV transmission line will run adjacent to the pipelines and supply power to the pump stations and mine area.
So what is the current progress on the ground? Teck continues to expect first production in the second half of 2022, with copper-equivalent annual production of 316,000 t for the first 5 years. Alexander Nicholas Christopher, Senior Vice President-Exploration, Projects & Technical Services, Teck Resources had this to say: “The project’s continuing to effectively advance construction with overall progress now past the two-thirds mark and we’re committed to achieving first copper as quickly as possible. To this end, we’re focused on the critical systems, which are the key enablers for commissioning and start-up to deliver first copper, and these are the desalination plant and associated port deployment infrastructure, the crushing, grinding and flotation systems at the concentrator, and the tailings management facility required for water storage. The project team is laser-focused on ensuring these three systems are delivered and commissioned on schedule to deliver first copper as soon as possible in the second half of 2022.”
The 143,000 t/d concentrator includes a grinding circuit consisting of two 12.2 m diameter by 6.7 m effective grinding length (EGL) 24 MW FLSmidth SAG mills driven by ABB gearless drives, each with a discharge trommel screen (6.2 m in diameter by 5.2 m long); four 7.9 m diameter by 12.8 m flange-to-flange length, 16.4 MW FLSmidth ball mills, also driven by ABB gearless drives; four cyclone feed slurry pumps, rated at 8,817 m3/h and 2,000 kW, with adjustable frequency drives; and four cyclone clusters with eleven operating and three standby 838 mm diameter cyclones in each cluster. The flotation circuit includes 14 FLSmidth 600 m3 bulk nextSTEP rougher flotation tank cells (two rows of seven cells) and eight bulk first cleaner Woodgrove Technologies Staged Flotation Reactor SFR-2200 cells (two rows of four cells); 10 bulk cleaner/scavenger SFR-2200 cells (two rows of five cells) and five bulk second cleaner SFR-1300 cells. The regrind circuit includes two bulk rougher regrind cyclone clusters and two 3,500 kW high-intensity grinding (HIG) regrind mills. There is one 43 m diameter bulk conventional concentrate thickener and one 43 m diameter copper conventional concentrate thickener, both with rakes and underflow pumps.
The tailings facility consists of two tailings thickeners and the associated equipment. The final concentrator tailings (combined bulk rougher plus bulk cleaner/scavenger tailings products), at approximately 28% solids, will flow by gravity from the concentrator flotation area via a lined launder to the tailings thickener distributor box. The tailings thickening area has two 85 m diameter, high–rate tailings thickeners.
A September photo showed the truck shop, which, along with the mine electrical loop, are some of the early components that will be completed and commissioned in the fourth quarter of this year to support pre-stripping activities. Other systems, such as the power substations, are also nearing completion to support commissioning activities. An aerial view of the primary crusher from October was also shown, where civil and structural works are nearing completion, and Teck says it is getting prepared to install the 1.2 km overland conveyor, which will transport crushed ore to the stacker structure, which in turn will deliver the crushed ore to a dome covered stockpile. With regard to the mining fleet, the first of 28 autonomous Caterpillar 794 AC trucks began arriving in May 2021. These are already being used to deliver rockfill to the tailings dam but will ulitmately form the heart of the open pit operation which at its peak will handle 120 Mt/y.